Bikkurim 3:1

First fruits are separated as follows: when a person enters his field and sees a ripe fig, pomegranate or cluster of grapes, he ties a reed around it and says, “These are the first fruits.” Rabbi Shimon says that he designates them first fruits again when they are picked.

Bikkurim 3:2

First fruits are brought to the Temple as follows: people from all the cities in the same region would gather in the regional seat and spend the night in the town square; they would not enter any buildings (to avoid the possibility of becoming ritually impure should somebody die). Early in the morning, the regional head would recite Jeremiah 31:5, “Arise and we shall go up to Zion, to the House of Hashem our God.”